Many American women have this vision of a French woman sitting down in a café each morning with her croissant and cappuccino, then going about her day and coming home to a giant plate of steak frites. But if that's the case, how could she possible stay so thin? It has to be a French thing, we tell ourselves, knowing full well that French women are no biologically different than ourselves.

So what is the secret that keeps their tummies so enviously flat? “It’s really a three-pronged approach, including stress and sleep management, diet, and exercise,” says Valerie Orsoni, a Parisian native and founder of the popular weight-loss program LeBootCamp.com. In her new book, LeBootcamp Diet, she highlights the scientifically-proven methods many French woman swear by for weight loss. We had her share her top tips for eating and living like a true Parisian. (Plus, 3 Food Rules You Can Learn From French Kids.)

Don’t think about fitness so much“French women don’t think about fitness as being in another box. It's just part of their life,” explains Orsoni (who was walking the entire time we chatted on the phone—genius!). She calls these simple get-fit tricks "25th hour exercises"—things you can do to engage your body while you’re doing other things. Squat when you pee instead of sitting (seriously), contract your abs every time you walk through a doorway, do 50 jumping jacks before breakfast, and walk over to talk to someone instead of sending an email. Small exercises like this seamlessly work into your day and increase your movement, so you can burn up to 400 more calories a day, she says. And you don't necessarily have to budget extra time for the gym. (Get more easy fitness tips as Celebrities and Their Trainers Reveal: Healthy Habits That Last a Lifetime.)

Pay attention to portionsPortions in the U.S. are almost twice the size of those in France, says Orsoni, who learned that the hard way when she moved to America and gained weight from the unusually large servings. Use simple portion guidelines—like protein the size of a deck of cards and a serving of cheese half that size—then pile on the veggies! French women don’t have forbidden foods, but they do stick to small servings of indulgent dishes.

Pay attention to glycemic loadWhen Orsoni started looking at the typical French diet, she noticed the most popular foods had a naturally low glycemic load. Glycemic load (GL) measures the impact a food has on blood sugar—those with a lower GL have a higher water and fiber content, which aid in weight loss. A typical low GL day for a French woman might start with a buckwheat pancake with strawberry jam or a fruit and yogurt, then a lunch of leek salad, grilled fish or meat, and a very small portion of French fries (yes, they still eat them!), followed by a scallion omelet and side salad for dinner with a pear for dessert.

Don’t rely on supplementsThose beautiful outdoor markets you see in photos of France aren’t just for show. They’re the health food stores of the nation. “French women don’t believe in taking extra supplements or quick fix diet pills. They know a magic pill is too good to be true,” says Orsoni. Instead, they get their vitamins and minerals from whole foods. (Just watch out for 6 Weight Gain Traps to Avoid at the Farmers Market.)

Turn off after hours“In France, when you are out of the office, you are really out of the office,” says Orsoni. Trying to juggle work and your personal life at the same time leads to stress, which increases your cortisol levels, she explains. And high levels of cortisol levels cause your body to store fat around the abdomen. By worrying less about work-related things during your time off, your body will hang on to less fat.

Sleep without distractionsAmericans are much more connected to their electronic devices than the French, Orsoni has noticed. “Americans usually go to bed with their cell phone on the night stand, and if they wake up in the middle of the night, they will check their phone. This leads to disturbed sleep patterns that maks it harder to be active the next day, since you wake up less refreshed. French women, on the other hand, have no problem shutting off their phone before bed or setting it in another room to charge." (It's one of the 8 Secrets Calm People Know.)